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During the summer of 2016, the Hawaii Department of Health responded to the second-largest domestic foodborne hepatitis A virus (HAV) outbreak in the post-vaccine era. The epidemiological investigation included case finding and investigation, sequencing of RNA positive clinical specimens, product trace-back and virologic testing and sequencing of HAV RNA from the product. Additionally, an online survey open to all Hawaii residents was conducted to estimate baseline commercial food consumption. We identified 292 confirmed HAV cases, of whom 11 (4%) were possible secondary cases. Seventy-four (25%) were hospitalised and there were two deaths. Among all cases, 94% reported eating at Oahu or Kauai Island branches of Restaurant Chain A, with 86% of those cases reporting raw scallop consumption. In contrast, a food consumption survey conducted during the outbreak indicated 25% of Oahu residents patronised Restaurant Chain A in the 7 weeks before the survey. Product trace-back revealed a single distributor that supplied scallops imported from the Philippines to Restaurant Chain A. Recovery, amplification and sequence comparison of HAV recovered from scallops revealed viral sequences matching those from case-patients. Removal of product from implicated restaurants and vaccination of those potentially exposed led to the cessation of the outbreak. This outbreak further highlights the need for improved imported food safety.
Much of the interest in youth at clinical high risk (CHR) of psychosis has been in understanding conversion. Recent literature has suggested that less than 25% of those who meet established criteria for being at CHR of psychosis go on to develop a psychotic illness. However, little is known about the outcome of those who do not make the transition to psychosis. The aim of this paper was to examine clinical symptoms and functioning in the second North American Prodrome Longitudinal Study (NAPLS 2) of those individuals whose by the end of 2 years in the study had not developed psychosis.
In NAPLS-2 278 CHR participants completed 2-year follow-ups and had not made the transition to psychosis. At 2-years the sample was divided into three groups – those whose symptoms were in remission, those who were still symptomatic and those whose symptoms had become more severe.
There was no difference between those who remitted early in the study compared with those who remitted at one or 2 years. At 2-years, those in remission had fewer symptoms and improved functioning compared with the two symptomatic groups. However, all three groups had poorer social functioning and cognition than healthy controls.
A detailed examination of the clinical and functional outcomes of those who did not make the transition to psychosis did not contribute to predicting who may make the transition or who may have an earlier remission of attenuated psychotic symptoms.
Adolescence is a critical time point in the lifecourse. LifeLab is an educational intervention engaging adolescents in understanding Developmental Origins of Health and Disease (DOHaD) concepts and the impact of the early life environment on future health, benefitting both their long-term health and that of the next generation. We aimed to assess whether engaging adolescents with DOHaD concepts improves scientific literacy and whether engagement alone improves health behaviours.
Six schools were randomized, three to intervention and three to control. Outcome measures were changed in knowledge, and intended and actual behaviour in relation to diet and lifestyle. A total of 333 students completed baseline and follow-up questionnaires. At 12 months, intervention students showed greater understanding of DOHaD concepts. No sustained changes in behaviours were identified.
Adolescents’ engagement with DOHaD concepts can be improved and maintained over 12 months. Such engagement does not itself translate into behaviour change. The intervention has consequently been revised to include additional components beyond engagement alone.
Following the B777 accident at Heathrow in 2008, the certification authorities required Boeing, Airbus, and Rolls-Royce to conduct icing analysis and tests of their Rolls-Royce Trent engined aircraft fuel systems. The experience and the test data gained from these activities were distilled and released by Airbus to the EASA ICAR project for research and analysis. This paper provided an overview of the Airbus ice accretion and release tests. Brief narratives on the test rigs, the test procedure and methodology were given and key findings from the ice release investigations were presented. The accreted ice thickness was non-uniform; however, it is found typically c.
thick. Analysis of the accreted ice collected from the rig tests showed the ice was very porous. The porosity is very much dependant on how the water was introduced and mixed in the icing test rigs. The standard Airbus method produced accreted ice of higher porosity compared to that produced by the injection method. The porosity of the accreted ice from Airbus icing investigations was found to be c. 0.90. The relationship of permeability with porosity was inferred from published data and models for freshly fallen snow in the atmosphere. Derived permeability
was then applied in the CFD analysis of pipe flow with a porous wall lining to determine the shear stress on the accreted ice. It showed that 25%, 50% and 75% of the accreted ice has interface shear strength of less than
The application of modern process control techniques to poultry production is outlined. Compact dynamic data-based models are proposed to describe and control the metabolic responses of broiler chickens to variations in the micro-environment. The dynamic response of heat production to step changes in air temperature and light intensity could be modelled with a , on average, of 0.83 and 0.93 respectively. Using recursive parameter estimation techniques, the time-variant response of animal growth to food supply could be predicted on-line with a prediction error of a maximum of 5%, three to seven days ahead depending on the type of feeding schedule. We argue that the potential conflicts between the environmental, financial and biological pressures on sustainable poultry production can be resolved through the development of integrated management systems using process control techniques.
This review considers the likely impact of changing consumer requirements, political pressure, economics and technological advances on the dairy production industry of the future. The vision is one of diverse strategies of production, the majority of milk being produced from cows managed technologically with much greater regard for welfare, with a number of ‘romantic’ strategies such as organic, extensive or dual-purpose production supplying niche markets. The important novel feature of the technological strategy will be an escape from the intensive twelve-month lactation cycle to extended lactations of, say, eighteen months, since this will reduce the number of times the cow is exposed to metabolic and other stresses associated with parturition, peak lactation and rebreeding.
Scientists have long known that certain pesticides, industrial chemicals and heavy metals have a detrimental impact on the reproductive health of a wide range of species (including humans) by disrupting the endocrine system. As exposure to, and the effects of, ‘endocrine disrupters’ are likely to be more pronounced in wild species with a short gestation period and life-cycle we have chosen to develop non-invasive tools based upon faecal steroid analysis to monitor the reproductive status of the short-tailed field vole (Microtus agrestis). This approach is hoped to eventually provide a sensitive means of detecting environmental disturbances that could adversely affect humans, livestock and wildlife by establishing the the field vole as a terrestrial biomarker. Faecal steroid hormone analysis has already been demonstrated as being a convenient and reliable means of diagnosing reproductive state in a large range of mammalian species (including gazelle, rhino, macaque and mice), however, as of yet little is known regarding the hormonal changes that occur during pregnancy in M. agrestis.
Livestock systems are comprised of sets of complex interconnected processes each with their own outputs eg growth, yield, animal health, welfare and environmental emissions. Livestock management decisions are currently based almost entirely on the judgement and experience of the stockman who has to estimate or guess the likely effects of any control action.
An integrated management system for a livestock production enterprise would be one which controlled all relevant processes. For example if the purpose of the system was to regulate nutritional input in order to control animal growth and pollutant emissions, the controller would calculate input values which would enable growth and emissions criteria to be satisfied simultaneously.
The essential components of an integrated management system are sensors and models. Developments in sensor technology will make available increasing amounts of information relevant to monitoring animals and their environment. Model-based control systems are particularly appropriate for accommodating the variability of most livestock production processes. Models exist for most of the economically important and scientifically interesting processes in livestock production. However the requirements of a process model that is to be incorporated into a controller are different from those of a model which is aimed at demonstrating understanding of the process. Areas where process models are lacking include those involving interactions between production and environmental factors.
The pre-requisites for nutritional management of dairy cows are information about how much feed is being consumed as well as the nutrients that are being derived from that feed. Studies of feed intake and nutrient supply have been limited by difficult experimental techniques, particularly with grazing animals. The models derived from much earlier work are of only general applicability and there is a need for more site-specific information in order to benefit further from conceptual advances.
We have adopted a different approach to studying herbage intake and nutrient supply, using less-invasive approaches as well as techniques that monitor more accessible aspects of these processes, such as jaw movements. These techniques have a major advantage, in addition to their value as research tools, because they could translate directly into commercial applications in on-farm monitoring. The use of diagnostics and behavioural recording is well explored in relation to health monitoring; here we argue for its potential to advance the application of knowledge about grazing and nutrition. We will illustrate this approach using our experiences in measuring grazing behaviour, using IGER behaviour recorders and assessing rumen function, using a series of non-invasive techniques.
The IGER grazing behaviour recorder allows us to record jaw movements and hence grazing and ruminating time and bite dynamics. It also allows the recording of steps and is now being developed to incorporate non-invasive rumen state sensors. It has made a major contribution to our understanding of the foraging strategies of grazing animals and their effect on herbage intake. This technology has the potential to be developed for on-farm monitoring of foraging behaviour providing valuable inputs to the prediction of herbage intake, in decision support systems for grazing.
The introduction of concept of protein degradation and microbial synthesis in the rumen are significant advances in protein rationing schemes. However, real progress has been limited because the lack of consistent experimental results means that models have little relevance to specific farm situations. We foresee considerable opportunities to monitor products of rumen degradation and synthesis that appear in milk (e.g. odd-chain fatty acids) or breath (e.g. sulphides).
Taken together these technologies open the possibilities of an entirely new approach to nutritional management of dairy cows, with site-specific recommendations based on information gathered using new sensors that are incorporated into computerised feeding equipment and milking parlours.
Current commercial poultry production in the UK faces many challenges which make it difficult to confidently predict the future. Changing legislation, responding largely to welfare pressures, is one such challenge. Additionally, consumer demands are widening. Eggs and meat from stock which is organically produced, or fed on rations containing no genetically modified ingredients, or free range produced, or corn fed are some of the assurances sought by the purchaser and consumer. Although the market place already offers such produce it is difficult to predict the extent to which they will penetrate a market which developed largely through the use of intensive production systems. The alternatives to intensively produced eggs and meat are more expensive to produce and therefore purchase and consequently are susceptible to changes in standards of living and the affluence of the consumer.
This paper briefly describes current commercial practices and some of the specific challenges arising from new legislation.
A description of some specific requirements of birds highlights areas where improvements, in terms of performance, production efficiency, and welfare might be gained. Since the overwhelming majority of eggs and meat is produced in intensive, highly automated systems, there is an obvious need for an integrated approach featuring engineers and the poultry industry to refine and further develop technology which better serves the birds, and ultimately, the consumer.
It is concluded that the UK cannot compete in production costs with some other areas of the world and as retailers increasingly source their goods worldwide, the UK poultry producer may have to resort to the production of products which satisfy niche demands.
Achieving adequate fertility is essential in any dairy unit, but is compromised by genetic selection for increased yield. Selection has altered the somatotrophic axis and resulted in cows which mobilise more body tissue for milk production in early lactation, thus prolonging both the depth and duration of the post partum negative energy balance. Poor energy status is reflected in altered metabolic parameters including raised urea and decreased insulin-like growth factor-I (IGF-I) and insulin concentrations, which adversely affect ovarian cyclicity and early embryo survival. Attempts to optimise the diet in terms of energy and protein content have generally been aimed at increasing milk production further rather than improving fertility. Advances in biosensor technology now provide us with the opportunity to monitor production, fertility and health parameters of each cow. Integration of this information should improve the timing for inseminations and could assist in selecting diets more suited to the needs of the individual cow. Genetic selection may in future be used to produce cows optimised for a particular type of management system. In both cases we need a greater understanding of the rules governing nutrient partitioning at different stages of the cows' life cycle to ensure that diets selected are cost effective and achieve an appropriate balance in promoting production, reproduction and health.
While preparing to write a vision of pig production in the UK, the fragility of crystal ball gazing became apparent, when in February 2001, the nightmare scenario of Foot and Mouth disease broke. The problem appears to have started on a pig farm using swill feed in Northumberland and within weeks, primarily associated with the farmer's failure to report a problem and legal but uncontrolled sheep movement, Foot and Mouth Disease spread throughout the West of England, Wales and the South West of Scotland as well as closing a major slaughterhouse for adult pigs. The disease then spread into continental Europe, causing instant havoc to export markets for the UK and then over the whole of the European Union. Had the problem prevented Denmark from exporting globally for any period, this would have resulted in severe price depression in pig production in Europe. And all this in the year following East Anglia's savaging with Classical Swine Fever.
The Foot and Mouth epidemic in the UK is likely to have a long term impact on the country's export capabilities; already there are threats of five year bans from countries like the United States of America. Much will depend on whether natural wildlife, such as deer, have become infected and how effective we are at finding carrier animals.
In pigs, variation in appetite under ad libitum feeding conditions is often associated with variation in carcass composition and meat quality. Breeds, strains and pigs types possessing high appetites are frequently fatter and have better meat quality (e.g. lower PSE incidence and more juicy meat) than those possessing low appetites, although for different physiological reasons. These conclusions are based on published reports of performance, carcass and meat characteristics in the following pig types: carriers of the halothane gene, Pietrain and Duroc breeds, animals selected for low backfat thickness and entire males. Selection schemes which reduce carcass fatness yet increase appetite are preferable to those which depress appetite so far as meat quality is concerned.
Livestock production under Northern European conditions can affect water, air and soil. Examples of the possible environmental effects on water are fish kills or microbial contamination, if solid manure, slurry, “dirty water” or silage effluent are collected, stored, handled or spread inappropriately. Examples of the possible environmental effects on air are emissions of ammonia (which can lead to acidification and, after subsequent deposition, to eutrophication), the greenhouse gases methane and nitrous oxide, odours and particulates.
In the case of water pollution, good management practices using existing technology are usually adequate for preventing most environmental impacts. This often requires storage during periods when conditions are unsuitable for spreading, followed by carefully controlled application. However, for relatively dilute effluents (such as dairy farm “dirty water”), it may be more cost-effective to use different approaches, such as waste minimisation and/or continuous treatment and land spreading. Recent research results are reviewed and compared in this paper, to identify ways in which farmers can prevent water pollution at least cost. The potential implications of such measures on further reductions in the annual numbers of pollution incidents are discussed in conjunction with the impacts of different regulatory and punitive approaches.
In the case of preventing air pollution, although good management can achieve much, there is a need for new technology to back it up. Existing ammonia abatement techniques are mostly expensive and farmer-unfriendly. In the longer term, changes to the animals' diet should hold the greater potential for abatement, not only of ammonia emissions but also of methane emissions. Reducing one form of pollution can often increase another, so an integrated approach to solving pollution problems is necessary.
The agricultural industry, particularly the livestock section, has been beset by difficulties in recent years, with the wettest year since 1776, the lowest commodity prices since the 1930's in many sectors, and by the widespread outbreak of ‘foot and mouth’ disease (F&M). This epidemic renewed fears for the future in an industry that was just beginning to see a glimmer of hope for better times ahead after many years of depression, with the OECD forecasting in early 2001 that world agricultural markets were poised for a ‘significant recovery‘.
Following what with hindsight can be thought of as a ‘golden period’ in the early 1990's, things began to go really wrong in the livestock sector after the BSE crisis in 1996. The problems were exacerbated by many other ‘external economic’ pressures in the late 1990's - in particular the high value of the pound and its effect on trade and market prices, the economic problems in other parts of the world (particularly in South East Asia and the former Eastern bloc), and an oversupplied European food market (particularly for meat and dairy products). By the late 1990's these ‘macro’ pressures were affecting all livestock sectors and if things were not bad enough, the spectre of ‘disease’ was about to make matters worse, beginning with the outbreak of classical swine fever in the pig industry in 2000.
The downward pressure on market prices and the monetary losses have also brought into focus the structural changes that are sorely needed throughout the livestock production, and meat processing/marketing supply chains in Britain. It has been apparent (ignoring the international situation) since the late 1980's, following the more rapid changes that have occurred in the final domestic consumer market, that these have been needed and they are now essential if the industry is to remain competitive in the 21st century.
This paper concentrates on livestock production systems by introducing sustainable housing characteristics, and the type of information required to make an informed choice on environmentally sound materials and systems. It then compares energy use in two contrasting beef cattle systems, one a conventional straw-bedded court and roofed silo, with feed delivered by a side-delivery wagon, and the other a roofless woodchip corral and earth-bank silo, with feed delivered by fore-end loader. The woodchip corral system requires 70% less energy than the conventional bedded court, when the total energy inputs are analysed for preparation of the building materials, construction of the livestock accommodation with associated feed and waste storage, and manufacture and operation of machinery. However, when energy used in feed production is included this dominates the energy budget, accounting for 60% of all energy used in the conventional bedded court, and 85% of energy used in the woodchip corral system.
This study compared the effect of feeding AmyPlus, a moist feed, as opposed to rolled wheat on the yield and composition of milk from dairy cows consuming grass silage based total mixed ration (TMR). Seventy-two Holstein-Friesian cows were distributed into AmyPlus (Treatment) and Wheat (Control) groups and loose housed on straw in an open shed. Each kg Wheat based concentrate contained 345g rolled wheat, 230g rapeseed meal, 115g sugarbeet pulp, 115g Molaferm 20, 115g soybean meal, 56g barley straw and 24g vitamin-minerals. In contrast, each kg AmyPlus based concentrate contained 501g AmyPlus (480g DM /kg), 105g rapeseed meal, 126g sugarbeet pulp, 126g Molaferm 20, 84g soybean meal, 41g barley straw and 17g vitamin-minerals. Here, AmyPlus was loaded directly into the mixer wagon to prepare fresh AmyPlus based TMR with a silage to concentrate ratio of 68:32. Each TMR was fed once daily to the corresponding group of cows also receiving 2kg of Distillers’ grains per cow in the parlour during milking. Daily milk yield and composition was recorded from November 1999 to February 2000. The overall daily Dry matter intake (DMI) of each TMR per cow remained uniform (20.19 vs 20.15 kg for Treatment and Control group respectively) across both groups. Daily milk yield and total cell counts per cow did not vary significantly (P>0.05) between groups during various months. While, milk fat and protein contents were greater in Treatment than Control group during each month, the differences were significant (P<0.05) only during November and December for fat and in January for protein. On average, the Treatment group tended to show a non-significant increase (P>0.05) in daily milk yield per cow by 0.144 kg than the Control group. The fat (46.2 vs 43.7) and protein (34.5 vs 33.5) contents in g /kg milk were also increased significantly (P<0.001) in Treatment compared with Control group. Total cell counts did not vary significantly (P>0.05) and remained within the acceptable limits. The cows consuming AmyPlus maintained their health as indicated by their intake, production, cell counts and general appearance. It would appear that AmyPlus can replace rolled wheat in TMR. However, it may be necessary to evaluate the storage, economic and environmental implications of using such moist co-products in silage based dairy rations.
Reliable and affordable technology for collecting and managing livestock production process information is being developed. The advances in data measurement, collection and transfer technology enable us to retrieve information from one or more remote sites to be processed and managed centrally. This opens up the opportunity to advance from open loop, prescriptive production to closed loop systems where factors influencing the actual performance of animals are used to modify and improve their production parameters (feed, environment, medication). We strive from producing animals by predicting what is needed using outdated data, to measuring what is actually happening as they grow, processing this information and acting to optimise animal performance by modifying production parameters in real time.
This paper describes commercially available systems that make possible the retrieval, collection, processing and distribution of near real time production information. Various aspects of production management using this technology are discussed, and examples of how it can be applied to monitor water usage, how it relates to pig performance and how energy usage can be influenced, are considered.
This experiment was conducted to evaluate the effect of adding some herbal feed additives (HF A) [thyme (T, Thymus Vulgaris L.), dianthus (D, Delphinum Ajaews), and fennel (F, Foeniculum Vulgare L.)] at a level of 10g/kg to Japanese quail diets on performance and some metabolic functions. Adding HFA to the control diet improved (P<0.05) body gain, feed intake and feed conversion (feed/gain) efficiency. The birds fed dietary F additive exhibited the best (P<0.05) values of these parameters during the entire period (0 to 6 weeks of age), compared with other dietary treatments. There was an improvement (P<0.05) in total protein, globulin, and albumin for birds fed dietary T or F at six weeks of age. Birds fed on dietary F recorded the lowest (P<0.05) value of these components compared with other dietary treatments.